Method of condensing magnesium



Aug. 251936. F. R. KEMMER METHOD OF CONDENSING MAGNESIUM Filed April 7. 1933 a INVENTOR; flan Xi fim/wi/fl- Y ATTORNEY.

' Patented Aug. 25, 1936 UNITED STATES PATENT OFFICE METHOD or OONDENSINGMAGNESIUM Frank R. Kemmer, Larchmont, N. Y., assignor to American Magnesium Metals Corporation, Pittsburgh, Pa.,' a corporation of Delaware Application April 7, 1933, Serial No. 664,932

11 Claims.

4, 1931, and entitled Method of producing mag-- nesium, the present application being a continuation in part thereof. In said application I have set forth a process for electrothermally l producing magnesium vapors in a furnace and I have furthermore stated that in order to obtain the best results, it is necessary that the mixture of magnesium vapors and C0 issuing from the furnace be quickly cooled. The quick cooling is abmagnesium oxide and carbon to produce the gaseous mixture while proceeding .to the right as shown in the following equation:

above a temperature of 1,100 to 1,200 degrees C. reverses itself and goes to the left below these temperatures. The reverse reaction is extremely rapid and unless the exit gases are quickly and efiectively cooled it is impossible to obtain a major portion of coherent metal from said gases.

This invention therefore resides in a. method of dilution of the magnesium vapors asxthey issue I from theffurnace. f A relatively large amount of dilution not only interferes with the condensation of the vapors, but also tends to induce chemical reactions by reasons of thepresence of the diluting gases. For example, it has been proposed to add hydrogen to the vapors either in the furnace or at the exit from the furnace and applicant preferably avoids such additions for these and other reasons. Hydrogen and the like may form water with CO and this will react with the finely divided magnesium forming an oxide coating which greatly interferes with subsequent recovery of the metal, even if, present only in small amounts. If the dilution is large, difliculty arises in the handling of the large volume of gases, and in condensing the magnesium in desirable form.

In practicing this invention the mixture of gases issuing from the furnace is cooled from above the maximum reversion point to a very low temperature by causing the same to impinge upon or into a curtain or film of hydrocarbon oil or other liquid which is non-reactive with magnesium metal. The liquid need not necessarily be solutely essential because the reaction between I paratus made in accordance withthe present ini Fig. 2.

non-volatile at said temperature, but preferably so. The liquid should be such as will wet the magnesium powder and thus form a film thereover and protect the powder from oxidation. At the same time the liquid should permit the escape 5 of CO gas. The liquid should be capable of carrying the magnesium powder to a collecting apparatus. While it is not at all essential it is preferred to cool the liquid so as to maintain. its temperature as near normal as possible thus increasing the eificiency of the operation.

As a specific example there was used a kerosene oil at a temperature of 8 C. which was allowed to flow in a thin film over a water cooled plate. The hot magnesium vapor impinging upon this moving film was instantaneously cooled to about 31 C. while the oil was simultaneously heated to the same temperature. Any vapors produced may be recovered, as is well known.

The magnesium powder mixed with oil may then I be taken to a storage bin and then utilized for further operations. The use of the oil or other liquid has the effect of not only quickly cooling the magnesium, but also of. separating it from the 00 which is not, soluble in, nor is held by the oil. I The oil furthermore protects the magnesium so that it may be kept in storage for as long a time as desired without danger of oxidation by air. Such oxidation proceeds with a fair degree of rapidity when the magnesium powder is not .so protected and is exposed to air at ordinary temperatures. The oil further has an important function in the subsequent treatment of the magnesium powder to produce coherent metal as described in my co-pending application Serial- #664,- 933, filed April 7, 1933, now Patent No. 1,964,833, granted July 3, 1934 and entitled "Method 'of making liquid magnesium. The oil in this operation provides a neutral or slightly reducing atmosphere and also provides a slight pressure to keep out air and thus facilitates the production of liquid metal in the stated apparatus.

In the accompanying drawing constituting a part hereof andin which like reference char-' acters indicate like parts:

Figure 1 is a perspective view of a suitable apparatus,

Figure 2 is afront elevational view of the apvention, and

Figure 3 is a p section on the line IIIIII of The apparatus consists essentially of a plate I," held in a substantially vertical position. At the upper end thereof are a series of pipes 2, the open ends 3 of each are compressed and flattened as shown in Figures 2 and 3 to provide nozzles giving a thin, widely spread film of oil over the surface of the plate [.3 A pipe 4 leading from the furnace and containing hot magnesium vapors mixed with CO terminates in close proximity to the plate I. A jacket 5 secured to the back of plate I and of relatively narrow cross-section has a bafile 5 therein terminating at point 1, below the top of the water jacket. An inlet pipe 8 is provided on one side of the bafile 6 near the bottom of the jacket for the entrance of water, and a similar pipe 9 on the opposite side of the baflle 6 for the outflow of water. Rivets ID are provided at various points to hold the jacket and the plate in fixed relativepositions and to prevent warping or distortion of the plate. The lower end of the plate and jacket is tapered as shown in Figure 1, and is provided with walls I I constituting a receptacle to catch the mixture of oil and magnesium, which flows out through opening [2 and into a suitable storage bin. Wings 13 and I along the sides of the plate, and constituting an extension of the side walls ll, act as guards to prevent splashing of oil and thus loss of-material. Extensions IS on the top of the apparatus provide means for holding the same in the proper position.

In operation of the invention kerosene oil is caused to fiow through pipes 2 and through the nozzles 3 which cause the oil to spread over substantially the entire surface of plate I and to fiow down the plate. Hot magnesium vapors mixed with CO from pipe 4 impinge upon the film of oil and the particles of magnesium are instantaneously condensed and are surrounded by films of oil. The CO gas escapes from the surface of the plate and may be removed as desired. The oil fiows into the container at the bottom of the plate and through opening l2 to storage. There is no necessity for any rapid recovery of the magnesium from the storage liquid nor is it necessary to take any precautions against oxidation thereof as the magnesium powder is perfectly preserved in the oil.

By this treatment it is possible to place the condenser arrangement close to the furnace and therefore the gases issuing from the furnace impinge upon the same at a relatively high temperature which decreases further the danger of reversion.

There are no difficulties introduced as occurs in other proposed methods wherein clogging of the exit pipe by condensed and reverted magnesium causes considerable difiiculty. By reason of this method of condensation the eventual recovery of. metal from the powder is very materially in-.

creased. a

Although I have described my invention setting forth a single embodiment thereof and indicating a type of apparatus which I have found to be useful in this operation, my operation is not at all limited to the details herein set forth, but is to be broadly construed. The invention is directed primarily to the extremely rapid cooling of vapors from high temperatures to below a reactive point and is also directed to the preservation of the condensed material against subsequent reactions. It will be apparent to those skilled in the art that various changes, omissions, additions and consolidations of method and apparatus may be made and still carry out the objects of this invention. For instance, other means for cooling the plate may be used. The plate may be omitted and the magnesium vapors may flowinto a freely falling curtainof oil or the like. Or the oil may be atomized or injected in finely divided form into the said vapors. In these cases the oil may or may not be previously cooled. as desired. 1. therefore, contemplate such changes as may be made for the carrying out of the present invention, the scope of which is not to be limited except by the claims appended hereto.

No claim is made herein to the apparatus described hereinabove and shown in the drawing, the subject matter having been transferred to a divisional application filed November 20, 1934, Serial No. 753,882.

What I claim is:-

1. A method of treating magnesium vapors in admixture with gas which comprises producing the same in a highly heated state, and quickly cooling the same by direct contact with a cooled hydrocarbon liquid adapted to protect the magnesium against oxidation.

. 2. A method of treating magnesium vapors in admixture with gas which comprises producing the same in a highly heated state, and quickly cooling the same by direct contact with a hydrocarbon liquid.

.3. A method of treating magnesium vapors in admixture with carbon monoxide, which comprises producing the same in a highly heated state and quickly cooling the same by direct contact with a hydrocarbon liquid from a temperature above the range of temperatures within which the reversible reaction MgO+Cr Mg+CO proceeds from right to left, down to a non-reactive temperature.

4. A method of treating magnesium vapors-in admixture with gas which comprises producing the same in a highly heated state, and quickly cooling the same'by direct contact with a hydrocarbon liquid to substantially room temperature.

5. A method of treating magnesium vapors in admixture with CO gas which comprises producing the same in a highly heated state in the absence of large amounts of other gases, and quickly cooling the same by direct contact with a hydrocarbon liquid.

6. A method of treating magnesium vapors in admixture with gas which comprises producing the same in a highly heated state, providing a film of hydrocarbon liquid, and causing said vapors to come in contact with said fihn.

'7. A method of treating magnesium vapors in admixture with gas. which comprises producing the same in a highly heated state, providing a continuously moving film of hydrocarbon liquid, and causing said vapors to come in contact with said film.

8. A method of treating magnesium vapors in admixture with gas which comprises producing the same inahighly heated state, providing acooled film of hydrocarbon liquid, and causing said vapors to come in contact with said film.

9. A method of treating magnesium vapors in admixture with carbon monoxide which comprises producing the same in a highly heated state and quickly cooling the same by direct contact with a free falling curtain of hydrocarbon liquid.

10. A method of treating magnesium vapors in admixture with carbon monoxide, which comprises producing the same in a highly heated state and quickly cooling the same by injecting 

